RU2335256C2 - Device for treatment of spine fractures - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: device contains bone screws, U-shaped couplings, clamps, bandages, screw-nuts and rod. Bone screw is made with spherical head. U-shaped coupling is made with slot for rod and can be put on bone screw. Clamp can be inserted into screw-nut, the latter can be screwed into U-shaped coupling. Rod has supporting spherical divided rings for clamp. Rod is made with transversal grooves. Said rings are made with internal ring projection which can be inserted into transversal grooves on the rod. Bone screw is made with sphere into the head. U-shaped coupling is made with external cone section. Bandage can be put into screw-nut and tightened on said cone section. Clamp is made with projections, bent from axis, and can lock said ring.

EFFECT: enhancing fixation reliability and simplification of installation of construction for spine fixation.

5 dwg

Description

The proposed technical solution relates to medical equipment, namely to traumatology and orthopedics, and is intended for the treatment of spinal injuries.

The existing system of fixation of the spine "Diapason" company "Stryker" contains rods, screws with a U-shaped head, a spherical ring, a lock, a lid, a jumper to connect the two rods. The presence of a split sphere allows the rod to be located at a certain angle to the axis of the screw. This system provides rod-screw fixation of the vertebrae. However, when tightened with a lock, the U-shaped screw has the ability to diverge and there is no reliable fixation of the screw to the shaft.

Also known is a system of multi-axis transpedicular screws (SMTV) containing screws, rods, nuts, transverse elements, couplings, etc. This Counter-Dubusse Horizont system manufactured by Medtronic Safomor Danek allows you to install a structure of rods and transpedicular screws with a special head configuration - “floating”, with the possibility of installing the screw axis at an angle of 25 degrees in all directions of rotation. Despite the fact that the screws can not be installed in one line, it is due to the design of the screw head that it is not necessary to bend the rods, trying to fully reproduce the sagittal profile of the spine. The screws are fixed with a double nut with a breakaway head.

Noting the positive aspects of the possibility of installing a screw with a rod in different planes, it is necessary to note some disadvantages. Due to the variability of the properties of the material of the double nut and the error in its manufacture, it is impossible to fix the screw reliably, because the nut breaks when a certain torque is reached.

The closest analogue (prototype) of the proposed technical solution is a device for the treatment of the spine - (Application WO 2005/096974/2005), containing, inter alia, bone screws, U-shaped couplings, clamps, braces, nuts and a rod. The bone screw is made with a spherical head, the U-shaped coupling is made with a groove under the shaft and can be put on the bone screw, the clip has the ability to be inserted into the nut, and the latter has the ability to screw into the U-shaped coupling. This device is convenient in operation, fixes the rod in one step. The disadvantage of this device is that during assembly there is a possibility of thread failure of the U-shaped coupling.

The aim of the proposed technical solution is to increase the reliability of fixation and simplify installation.

This goal is achieved by the fact that in the device for the treatment of spinal fractures containing a bone screw with a spherical head, a U-shaped sleeve with a groove under the shaft, which can be put on a bone screw, the clamp has the ability to be inserted into the nut, and the latter has the ability to screw into U -shaped coupling. The rod has supporting spherical split rings under the clamp, which is made with transverse recesses. The said rings are made with an inner annular protrusion having the ability to enter the transverse recesses of the rod, the bone screw is made with a sphere inside the head, the U-shaped coupling is made with an external conical section, and the bandage has the ability to put on the nut and tighten on the said conical section, and the clamp made with protrusions bent from its axis, and has the ability to counter the mentioned ring.

Achieving this goal - increasing reliable fixation and simplifying installation is achieved by the fact that the spherical ring is made by a protrusion that enters the recess on the rod, while tightening, presses the rod against the U-shaped coupling and self-locks with protrusions bent from the axis. The nut, moving the brace on the conical surface of the U-shaped coupling, finally and reliably fixes the entire system as a whole. Simplification of the installation is achieved by combining the possibility of installing a screw with a spherical head and a rod with a spherical ring on a U-shaped sleeve, which helps to minimize the adjustment of the rod to the spine profile.

Compression-distraction is achieved by moving the bone screws along the axis of the rod with weakened clamps and nuts using a special device such as forceps. Then tighten the clamp and nut.

The ability to rotate the rod on spherical support rings and the polyaxial installation of bone screws greatly simplifies the assembly of the structure and fixation of the vertebrae.

Fixing the rod with recesses with the help of spherical rings with annular protrusions and a clamp with protrusions bent from the axis, as well as tightening the bandage on the conical surface of the U-shaped coupling, prevents the longitudinal movement of the vertebrae with screws during operation and increases the reliability of the design.

Figure 1 shows a device for the treatment of fractures of the spine, General view.

Figure 2 shows a longitudinal section along the axis of the rod, enlarged.

Figure 3 shows a spherical ring in section, enlarged.

Figure 4 shows a U-shaped coupling in section, enlarged.

Figure 5 shows the clip in section, enlarged.

A device for treating spinal fractures contains a bone screw 1 with a sphere inside the head, a U-shaped sleeve 2 with a conical section and with a groove for the shaft 3 with transverse recesses, covered by a spherical split ring 4, with an inner annular protrusion, a clamp 5 with a protrusion and a longitudinal section in it, bandage 6 and nut 7.

The proposed device for the treatment of spinal fractures is used as follows. With the help of an awl, a hole is made for the bone screw 1. A U-shaped sleeve 2 is put on this screw. Using a special screwdriver, screw 1 is screwed in the required direction into the vertebral body (previously). Then, gently, without injuring the nearby disc, another screw with a U-shaped sleeve 2 is screwed into another vertebral body. Correcting the angular position of the screws, screw 1 is finally screwed in with a special screwdriver. Having installed the sleeve 2 in such a position that it is convenient to insert the rod 3 with the spherical rings inserted into it 4. Next, put the bandage on the U-shaped sleeve 2 6 is screwed, with a special socket wrench, a nut 7 with a clip 5 inserted into it. With a special screwdriver, holding a special key by the rod 3, the clip 5 is finally screwed in. It is necessary that the end of the clip completely fits into the nut 7. Hold -hand rod 3, permanently screwed nut 7. At the same sequence is set half second structure which is connected to the previously collected by a cross member.

Compression-distraction is carried out with weakened clamps 5 and nuts 7, using a special device such as tongs, followed by tightening clamps 5 and nuts 7.

This design by fixing the screw 1 with a spherical ring 4, having an internal transverse protrusion on the rod 3, with transverse recesses by means of a clamp 5 with a protrusion from the axis, nut 7 and the band 5, worn on a conical surface on a U-shaped sleeve 2, securely fixes bone screw 1 on the shaft 3.

The combination of the possibility of a polyaxial installation of a screw 1 with a spherical head and a rod 3 with a spherical ring 4 on a U-shaped sleeve 2 contributes to the minimum fitting of the rod 3 to the sagittal profile of the spine and, thereby, simplifies the assembly of the structure.

Claims (1)

A device for the treatment of the spine containing bone screws, U-shaped couplings, clamps, braces, nuts and a rod, while the bone screw is made with a spherical head, the U-shaped coupling is made with a groove under the shaft and has the ability to put on the bone screw, the clamp has the possibility of insertion into the nut, and the latter has the ability to screw into a U-shaped coupling, characterized in that the rod has a spherical support split ring under the clamp, the rod is made with transverse recesses, said ring is made with an inner an annular protrusion having the ability to enter into the transverse recesses of the rod, the bone screw is made with a sphere inside the head, the U-shaped sleeve is made with an outer conical section, and the bandage can be put on the nut and tighten on the said conical section, and the clamp is made with protrusions bent from the axis, and has the ability to counter said ring.

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